Homologous Superfamily

Ribbon-helix-helix (IPR010985)

Short name: Ribbon_hlx_hlx

Overlapping entries


This superfamily represents domains with a ribbon-helix-helix core topology consisting of four helices in an open array of two hairpins. Such domains are found in several bacterial and phage repressors, including the Escherichia coli methionine repressor (MetJ), which when combined with S-adenosylmethionine (SAM) represses the expression of the methionine regulon and of enzymes involved in SAM synthesis [PMID: 1943695]. Other bacterial and phage repressors containing domains with a similar fold include the bacterial plasmid-encoded repressors CopG (IPR002145), the bacterial omega transcription repressor [PMID: 11733997], and the phage repressors Arc [PMID: 9927650] and Mnt [PMID: 7999761]. These repressors are usually obligate dimers, which pair through a single N-terminal strand, and possess a C-terminal helix-turn-helix unit [PMID: 15808743].

GO terms

Biological Process

GO:0006355 regulation of transcription, DNA-templated

Molecular Function

No terms assigned in this category.

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.